Salmon38 that PDF is interesting. And confusing for me.

I always used this reference.

There were 3 different ratio 8.2 Pontiac 10bolt carriers for both single track & Safe-T-Track usage
High ratio = 2.56-2.78
Mid ratio = 2.93-3.08-3.23
Low ratio = 3.36-3.55-3.90-4.11-4.33-4.56-4.88